-LRB- CNN -RRB- -- It 's not over in Steubenville , Ohio .

Although a judge has found two Steubenville teenagers guilty of raping a 16-year-old girl in a case that showcased jaw-dropping examples of teenage alcohol use and tawdry text messaging -- all wrapped in allegations of a cover-up -- Ohio 's attorney general said Monday it 's now time for a grand jury to look at whether anyone else should be charged .

`` I think the Steubenville community needs really two things . One is to get this over with , '' Attorney General Mike DeWine said in a nod to frustration the continued investigation is likely to cause in the city -- a small , down-on-its-luck Ohio River mill town that 's been the focus of intense criticism and media coverage for months .

`` But the other is to believe that justice has been done , that we have left no stone unturned and that anyone who is criminally liable has been brought to justice , '' he said .

Healing process after rape never ends

The victim 's mother told CNN that the verdicts are `` the start of a new beginning for my daughter . '' But she added , `` We need to stress the importance of helping those in need and to stand up for what is right . ''

`` We hope that from this something good can arise , '' she said . `` I feel I have an opportunity to bring an awareness to others , possibly change the mentality of a youth or help a parent to have more of an awareness to where their children are and what they are doing . The adults need to take responsibility and guide these children . ''

But the emotions inflamed by the case echoed past Sunday 's verdict , with sheriff 's deputies and state investigators arresting two teenage girls Monday for threatening the victim over Twitter . The girls -- one 15 , one 16 , both from Steubenville -- were in a juvenile lockup Monday night , awaiting an appearance before a judge Tuesday morning , Jefferson County Sheriff Fred Abdalla said .

Grand jury

DeWine said state investigators have examined tens of thousands of text messages , images and videos and talked to 56 witnesses -- from teenagers who attended the parties to assistant football coaches and the high school principal .

But 16 people who may know something about what happened that August night have refused to talk , he said .

`` I have reached the conclusion that this investigation can not be completed -- that we can not bring finality to this matter -- without the convening of a grand jury , '' he said in a statement Sunday .

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The grand jury will begin meeting around April 15 and could take `` a number of days '' to complete its work , DeWine said .

`` And I should point out that the convening of a grand jury , of course , does not necessarily mean that indictments will be returned or that charges will be filed , '' he said .

`` A grand jury is an investigative tool that is uniquely suited to ensure fairness and to complete this investigation , '' DeWine said in the Sunday statement . `` And this community needs assurance that no stone has been left unturned in our search for the truth . ''

Guilty verdicts

DeWine 's announcement of the grand jury came shortly after Judge Thomas Lipps found Trent Mays , 17 , and Ma ` lik Richmond , 16 , guilty of rape . Lipps , who was hearing the case without a jury , also found Mays guilty of disseminating a nude photo of a minor .

Authorities accused Mays and Richmond of putting their fingers in the girl 's vagina while she was too drunk to consent , an act that constitutes rape under Ohio law . The incident took place during a series of alcohol-fueled end-of-summer parties in August .

Some of the abuse was documented in photographs shown in court and in texts read aloud during testimony , including one text in which a state forensics investigator testified Mays wrote , `` I should have raped since everyone thinks I did . ''

Trial focuses on text messages

Lipps sentenced Mays to a minimum of two years in a juvenile correctional facility . Richmond received a minimum of one year . Juvenile authorities could decide to keep both in custody until they turn 21 .

Richmond 's father , Nathaniel Richmond , said he still believed his son was innocent `` even though he apologized in the courtroom . ''

`` The evidence they had against Ma ` lik was minimal , '' he told CNN 's `` Piers Morgan Tonight . '' `` Ma ` lik was just at the wrong place at the wrong time . I know my son is not a rapist , even though he has been convicted of rape . ''

Both Mays and Richmond must undergo treatment and will have to register as sex offenders , Lipps ruled . Richmond 's attorney , Walter Madison , said his client would appeal in an attempt to avoid that designation .

Meanwhile , the victim and her family remain under guard after the threats were posted online , Abdalla told CNN .

`` She continues to be a victim and be victimized ... over and over , '' he said . `` And that 's what 's sad . ''

One of the tweets that led to Monday 's arrests warned that if the poster saw the victim , `` it 's gone be a homicide . '' Another threatened a beating .

The girl accused of tweeting the death threat turned herself in after learning that investigators were looking for her , the sheriff said . Nevertheless , `` They 're going to have to answer to it , '' he said .

`` We 're dealing with kids , again , '' Abdalla said . `` But the attorney general had just left the building -- the judge was still in the building -- when I received messages that there 's death threats already against the victim . ''

No charges had been announced against the suspects Monday night , but `` There 's no question they 're going to prosecute . ''

`` I hope this sends a warning , '' he said . `` And I can assure you , we 've been monitoring Twitter for 24 hours and continue to . If there 's anybody else there crosses a line and makes a death threat , they 're going to have to face the consequences . ''

Internet outrage

The case received widespread attention after a blogger who once lived in Steubenville uncovered some of the materials posted to social media sites .

The blogger , Alexandria Goddard , wrote pointedly about the possibility that the teenagers had been given preferential treatment because they played on the town 's highly regarded football team . Police have denied that claim .

Later , the loosely organized hacker group Anonymous got involved , posting a lengthy video in which another teenager -- who has not been charged -- made joking references to the rape .

The ensuing ire over the case brought national attention and criticism to the city from around the country , leaving city officials struggling to defend the community and residents weary of the media spotlight .

Teen rape trial shines unwelcome spotlight on Ohio town

Broader problem

Acknowledging the town 's frustration , DeWine said Monday that it would be a mistake to focus on one small Ohio community , to think something unique in its culture is behind the incident .

`` I 'm afraid people are going to walk away and say this was all about Steubenville , '' DeWine said . `` It 's not . It 's a cultural problem . ''

`` I 'll guarantee that there are crimes very similar to this that occur every Friday night and every Saturday night in communities across this country where you have people , particularly young people , who are drinking too much and a girl is taken advantage of , and a girl is raped , '' he said .

Such incidents stem from a larger social problem -- a rampant lack of respect and human decency , he said .

`` One of the lessons of life is we have to take care of each other , and we have to try to help people and we have to do what 's right . '' DeWine said . `` And there were precious few people that night that were doing what was right . ''

Teens treated girl ` like a toy , ' prosecutor says

CNN 's Poppy Harlow , Brian Vitagliano , Yon Pomrenze , Matt Smith , Steve Almasy and Chelsea J. Carter contributed to this report .

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`` Adults need to take responsibility and guide these children , '' victim 's mother says

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Two Steubenville teens arrested after Twitter threats to victim , sheriff says

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Prosecutors will ask a grand jury to investigate the possibility of additional charges

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AG Mike DeWine says it would be wrong to blame Steubenville alone